An overview of the latest Lactobacilli and Bifidobacteria research.
Lactobacilli and Bifidobacteria are the most well-known genera of probiotic organisms that normally occur in the human gastrointestinal and genitourinary tracts. Many of the individual species for these two probiotic genera play important roles in promoting good health. These probiotics are also used therapeutically for the purpose of recolonizing the gut where they may have been depleted for one reason or another (e.g., antibiotic therapy, poor diet, etc.).
With the understanding that the body relies on these probiotics for multiple functions—including the absorption of nutrients, preventing colonization by pathogenic (harmful) bacteria, and metabolizing foods and certain drugs—recolonization is an important consideration. While probiotic strains are found in some fermented food products—e.g., yogurt, sour cream, kefir, sauerkraut, kombucha (fermented) tea and fermented soy (miso, tempeh), kimchi, etc.—they are more popularly consumed as an encapsulated, powdered, and even gummy supplement.
Is Probiotic Deficiency a Real Thing?
First off, can you really have a deficiency of probiotics?
Given that probiotics are not nutrients with a daily value, probiotic deficiencies in the human body are not always a topline nutrition subject. However, in the journal Current Opinion in Infectious Diseases, researchers noted that some inflammatory conditions of the gut are thought to be caused, at least in part, by “a relative deficiency of bifidobacteria”.1
In addition, there are negative ramifications to deal with when probiotics are present in insufficient quantities. An example of this is small intestine bacterial overgrowth syndrome (SIBO), a condition associated with the increase in pathogenic microorganisms. This occurs, in part, due to the fact that there are insufficient numbers of friendly, probiotic organisms to inhibit the spread of the harmful, pathogenic organisms.2 The result is an increase in chronic diarrhea, translocation of bacteria and their toxins from intestine to the blood, as well as intestinal absorption disorders causing vitamin B12–deficiency anemia, low levels of various vitamins, and protein deficiency.
A major strategy for decontamination of the small intestine in this instance is the use of probiotics (both after antibiotics and independently), which suppress the opportunistic pathogenic organisms, protect the mucous coat, improve digestion, and arrest diarrhea.3,4 The effectiveness of probiotics in correcting some of the previously mentioned nutrient deficiencies has also been seen in research where vitamin B12 and folate deficiencies where corrected in children supplemented with Lactobacillus acidophilus.5
So, in answer to the question, I’d say that a relative probiotic deficiency is a real thing.
Probiotics Use for a Wide Range of Disorders
Of course, probiotic supplementation has value beyond the prevention and treatment of probiotics deficiency. The fact is that probiotics have also been advocated for use in a wide range of disorders, with strong evidence to support efficacy. In fact, probiotics are now used extensively for this purpose6, and a significant amount of research has been conducted on different probiotic species in the Lactobacilli and Bifidobacteria genera for different purposes. Following is a brief overview of that research.
The Lactobacillus Genus
The Lactobacillus genus includes a group of lactic acid–producing probiotic species7,8 that make up many of the 400 normal probiotic species in the human body.7,9,10,11,12 Among the more important of these are L. acidophilus, L. rhamnosus, L. casei, and L. plantarum.
Lactobacillus acidophilus from yogurt has been shown to decrease the incidence of recurrent bacterial vaginosis.13 Laboratory research has also shown that L. acidophilus can inhibit the growth of the H. pylori bacterium14, which is implicated in the development of ulcers. In a irritable bowel syndrome, L. acidophilus has been shown to improve abdominal pain, bloating, number and quality of stools, and general physical state.15,16 A combination of L. acidophilus and L. casei was found to be effective in the treatment of bacterial overgrowth.17 In addition, L. acidophilus produces substances called bacteriocins, which act as natural agents against undesirable microorganisms.18 Furthermore, L. acidophilus has been shown to correct the increase of gram-negative bacteria which occurs following the use of broad-spectrum antibiotics given in the treatment of acute or chronic diarrhea.19-21
Lactobacillus rhamnosus is among the probiotics with the greatest number of proven benefits. Part of the reason for this may be that L. rhamnosus attaches to intestinal epithelial cells better than some other Lactobacillus species.22 Furthermore, randomized double-blind studies have provided evidence of L. rhamnosus effectiveness for the treatment and prevention of different types of diarrhea23, including antibiotic diarrhea24, chemotherapy-induced diarrhea25, Clostridium difficile diarrhea26, rotaviral diarrhea27, and traveler’s diarrhea28.
Lactobacillus casei may help reduce the frequency29 or severity30 of acute diarrhea in children aged 6-24 months. L. casei also adheres better to urogenital cells than other Lactobacillus species17, which may translate to preventing attachment by pathogenic bacteria. As noted previously, a combination of L. acidophilus and L. casei may be effective in the treatment of small intestinal bacterial overgrowth.31
Lactobacillus plantarum has been shown to reduce the severity of chemotherapy-induced enterocolitis32 (an inflammation of both the small and large intestine). Also, L. plantarum has been shown to inhibit attachment of E. coli to human colon cells.33 In a randomized, placebo-controlled trial16, L. plantarum was effective in significantly and rapidly reducing abdominal pain and flatulence in irritable bowel patients. At 12-month follow-up, those same patients maintained their improvement in overall gastrointestinal function. This probiotic may also be used to help prevent traveler’s diarrhea.16
The Bifidobacterium Genus
Bifidobacteria normally colonize in the human colon.34,35 Like Lactobacillus species, Bifidobacteria also produce lactic acid. These appear to be the most important organisms in the intestine in helping to create a microbial barrier to infection. Specifically, Bifidobacteria produce antimicrobial substances that are effective against many harmful gram-positive and gram-negative bacteria.34,36
Research indicates that supplementation with Bifidobacterium longum can reduce stool frequency, abdominal discomfort, and stool clostridial spore count in antibiotic-associated diarrhea37, although other research did not find the same significant reduction in diarrhea.24 Also, B. longum may ease gas and flatulence.38
A combination of Bifidobacterium breve, Bifidobacterium bifidum, and Lactobacillus acidophilus was shown to help prevent relapse and reduce disease activity in patients with ulcerative colitis when used as an adjunct to treatment with medication.39,40
Probiotic organisms of the Lactobacilli and Bifidobacteria genera normally occur in human beings and play important roles in promoting good health. Furthermore, probiotic deficiency—at least relative probiotic deficiency—is a real thing, and the use of a good probiotic supplement can help prevent and treat it. In addition, a significant amount of research has been conducted on different probiotic species in the Lactobacilli and Bifidobacteria genera, demonstrating that probiotic supplementation has value for a wide range of health purposes.
About the Author
Gene Bruno, MS, MHS, RH (AHG), is a certified nutritionist and registered herbalist with 42 years of dietary supplement industry experience. With a master’s degree in nutrition and a second master’s degree in herbal medicine, he has a proven track record of formulating innovative, evidence-based dietary supplements. Mr. Bruno currently serves as both the vice president of scientific and regulatory affairs at NutraScience Labs and professor of nutraceutical science at Huntington University of Health Sciences.